Universidade Federal De Lavras Research Articles

Produtividade do milho com base em uma abordagem de regressão distribucional

Abstract The objective of this work was to propose the use of traditional models based on distributional regression models to analyze maize productivity. The experiment was carried out in an alpha lattice design, with three replicates and 24 blocks. Data used refer to 102 maize plants from the permanent collection of the Centro de Desenvolvimento Científico e Tecnológico para a Agricultura of the Universidade Federal de Lavras. For the maize productivity evaluation, the following explanatory variables were used: weight of 100 seed, plant height, ear height, and days to maturation. The initial analyses involved the fitting of four distributions (gamma, generalized gamma, inverse Gaussian, and generalized inverse Gaussian) to the data, in which the gamma distribution showed the best fit based on the Akaike and Bayesian information criteria (AIC and BIC). Cob height has a considerable influence on the productivity variability because as cob height increases, the productivity variability decreases, whereas the covariates weight of 100 seed and days to maturity explain the increasing average of the productivity. The residual analysis shows that the model based on gamma distribution is suitable for explaining the data and providing useful insights for agricultural research and practice.

Síndrome da resposta inflamatória sistêmica: um fator de risco associada ao prognóstico desfavorável de cães infectados com parvovírus canino 2

ABSTRACT: Canine parvovirus 2 (CPV-2) is a highly contagious enteric virus that causes high morbidity and mortality, especially in dogs under six months of age. Recovery from this illness is dependent on several factors, including the patient’s prognosis for adequate therapy. The aim of this study was to evaluate the risk factors associated with the death outcome in CPV-2 positive dogs in a case-control study conducted at the Veterinary Hospital of the Universidade Federal de Lavras (HV-UFLA) in Lavras, Minas Gerais, Brazil. Twenty-six dogs with CPV-2 symptoms that arrived at the HV-UFLA between 2017 and 2018 were evaluated for inclusion in the study. Data on medical history, clinical signs, blood count and rapid test of parvovirus and faecal test for polymerase chain reaction (PCR) were collected for all the animals. All the dogs received treatment at the HV-UFLA, and the overall fatality rate due to canine parvovirus was 30.77%. Descriptive analysis and univariate and multivariate statistical analyses (logistic regression) were performed to assess the variables that were possibly associated with an unfavourable prognosis (death). In the univariate and multivariate analyses, Systemic Inflammatory Response Syndrome (SIRS) was observed to be a significant risk factor for an unfavourable prognosis in canine parvovirus, as it increased the risk of death by 12.96 times (95% CI 1.85-133.70; P < 0.01) compared with patients who did not exhibit SIRS. Thus, SIRS was strongly associated with an unfavourable prognosis, suggesting that it can be used as a prognostic indicator for canine parvovirus in veterinary practice.

Environmental and sociocultural issues: the movie "Brave New Land” (Brava Gente Brasileira) and dialogues with students in the Institutional Scholarship Program for Teaching Initiation (PIBID – Biology)

This work was carried out based on an analysis of the assessment made by students in the Institutional Scholarship Program for Teaching Initiation in Biological Sciences (PIBID) at the Universidade Federal de Lavras - MG (UFLA), where they presented their insights about the movie “Brave New Land” (Brava Gente Brasileira). The objective was to seek elements that demonstrate how the film dialogues with sociocultural and environmental issues, promoting addition to the training of biology teachers. With this goal, we used qualitative research that fits the content analysis, categorizing these students' common statements. We found 5 categories exposed in a frame, where we noticed how sociocultural issues stand out, however, the film brings relevant considerations about the Pantanal environment and the relationship between the traditional peoples with this place. Thus, it is possible to conclude that cinematographic art manages to dialogue and build a critical view of the relationships of the most diverse cultures with the collective and the environment.

Facing the COVID-19 pandemic with science and practice

The COVID-19 pandemic has led to a health system crisis, deaths and socioeconomic hardship. In order to minimize the consequences of the COVID-19 pandemic in the municipality of Lavras, a partnership was developed between the Lavras City Hall and the Universidade Federal de Lavras (UFLA). The present study aimed to describe the main prevention measures proposed in Lavras and to evaluate the community's perception of the management model towards COVID-19. A public online questionnaire, with 20 multiple-choice questions, about the measures to confront covid was submitted to the Google Forms platform from April 22nd to April 30th, 2020. The data regarding the strategies carried out to deal with COVID-19 was obtained from the published municipal ordinances. During the eight days that the questionnaire was applied, a total of 8,874 respondents from Lavras were obtained. Among these respondents, 31.64% (2,808) were men, 68.15% (6,047) were women, and 0.21% (19) declared "another option". When the participants were asked whether they are respecting the social distance measures, 7,452 (84.1%) of them answered "yes."Also, a total of 57.4% of the participants reported that the social distancing measures compromised their family income. However, despite the impact of this economic compromise on these families, 93.82% of the respondents believe that the measures applied are important. When analyzing the questionnaire responses, it was noticeable that despite residents suffering negative economic consequences, there was great popular approval of preventive measures, such as social distancing and the use of masks. In addition, it was possible to notice the population's trust in the measures recommended by professionals at UFLA and the city hall, highlighting the importance of establishing contact between authorities and the population during decision making.

Fatores de risco e enfermidades associadas a falha na imunização passiva natural em potros

ABSTRACT This study aimed to report the prevalence of diseases in foals, patients at the Hospital Veterinário de Grandes Animais, Universidade Federal de Lavras (HVGA-UFLA), and its association with deaths and possible failures in the transfer of passive immunity (FTIP) via colostrum. Data were obtained from clinical records of horses aged between 0 and 3 months, admitted to the HVGA between January/2014 and December/2018. Descriptive analyzes of the diseases and organ systems affected were performed, as well as univariate analyzes with chi-square or Fisher's exact tests, identifying possible associations between FTIP, infectious diseases and other factors. No significant relationships were found between FTIP and infectious disease, meconium retention, sepsis, or death. However, it was shown that animals weighing between 10 and 30kg were 29.333 times more likely (95% confidence interval 1.734 - 505.951) to die than those weighing between 30.1 and 130kg. Therefore, it can be concluded that low weight is a very relevant risk factor, which may be related to the failure of postural reflexes and, consequently, to the inability to ingest colostrum, impairing the ability to respond to infectious agents.

Scarabs in the dark: occurrence of Scarabaeoidea beetles (Insecta: Coleoptera) in Brazilian caves

Scarabeoidea (Insecta: Coleoptera) present more than 2000 species recorded from all over Brazil. They have been scarcely recorded from caves, and truly troglobitic species are yet to be found in the country. In this study, we carried out a review of all existing scarab beetles deposited until 2017 in the Coleção de Invertebrados Subterrâneos de Lavras (ISLA), at the Universidade Federal de Lavras (UFLA) (Minas Gerais, Brazil), one of the most important collections of subterranean invertebrates in South America. Ninety-two individuals belonging to 52 species were recorded, distributed in six families (Cetoniidae, Hybosoridae, Melolonthidae, Passalidae, Scarabaeidae and Trogidae). Scarabaeidae was the most diverse of them, representing more than 50% of the total of species recorded. We found Scarabeoidea beetles in 51 of the ~ 1600 caves examined, distributed in nine Brazilian states: Alagoas, Bahia, Distrito Federal, Espírito Santo, Goiás, Minas Gerais, Pará, Piauí, and Tocantins. Our results provide evidence that Scarabaeoidea beetles are not frequent in Brazilian caves, and their records in this kind of environment are mostly accidental. Exceptions include Trogidae and Aphodiinae species, which may be associated with bat guano. Our study presents the first list of Scarabaeoidea species sampled in Brazilian caves.

PREFACE: Proceedings of the XIV International Symposium of Neuropterology

The XIV International Symposium of Neuropterology (ISN) was held online, between May 23rd and 27th of 2022, with the Universidade Federal de Lavras, Minas Gerais, Brazil as responsible for the event. This event was carried out for and by researchers with interest in any aspects of biology, systematics, taxonomy, natural history, evolution, and applied studies on the insects of the superorder Neuropterida (Neuroptera, Megaloptera and Raphidioptera). This was the first meeting organized by a South American country, and the first one held online. A total of 141 participants from 24 countries attended the meeting, which was considered the largest number of registered participants among all the versions of the ISN and resulted in 10 keynote lectures (including the Opening Lecture), 21 oral presentations, and 17 poster presentations. The papers in this volume are representative of the lectures, oral presentations, and posters presented at the meeting. We dedicate these proceedings to the memory of the Professor and entomologist Dr. César Carvalho, who was directly responsible for bringing this meeting to Brazil, but unfortunately passed away in September 2018.

Identification of sources of resistance to race 63-63 of Pseudocercospora griseola in common bean lines

Angular leaf spot (ALS), caused by the fungus Pseudocercospora griseola, is one of the most important foliar fungal diseases in common bean (Phaseolus vulgaris L.). The search for new sources of resistance to ALS is a promising activity in common bean breeding programs. In this study, the reaction of 416 germplasm accessions from the Universidade Federal de Lavras (UFLA) to P. griseola (race 63-63, the most important and most aggressive race) was assessed under greenhouse conditions (plants in the V2 stage, fully developed unifoliolate leaves). We identified 102 (24.5%) resistant and 314 (75.5%) susceptible accessions. Among the resistant lines, more than half are Carioca grain type lines. This study characterizes the resistance of a wide collection of common bean genotypes. The identification of new accessions resistant to P. griseola is an important step in common bean breeding programs. These lines can continually be incorporated in backcrosses to obtain cultivars resistant to ALS.

Selection of superior sweet potato genotypes for human consumption via mixed models

The growing consumer demand for sweet potato roots results in the need for genotypes with higher yields and better root quality. Thus, the objective of this study was to agronomically evaluate sweet potato genotypes via mixed models to select superior genotypes for human consumption and predict their selection gains. The study had a partially balanced triple lattice design with three replicates. As treatments, 92 sweet potato genotypes from the Universidade Federal de Lavras germplasm bank selected in the first selection cycle were evaluated along with eight controls, namely, Brazlândia Roxa, Princesa, Uruguaiana, BRS Amélia, Beauregard, UFVJM-57, UFVJM-58, and UFVJM-61. The treatments were ranked by the mixed linear model via restricted maximum likelihood (REML) and best linear unbiased prediction (BLUP). We highlighted the 15 best genotypes for each agronomic trait, then identified the best ones overall considering all quantitative and qualitative traits. High heritability was found for the trait commercial root yield (56.31%). For all traits, there were selection gains relative to the population mean. The use of mixed models was efficient for the selection of superior sweet potato genotypes. The genotypes 2018-19-464, 2018-72-1409, 2018-72-1428, 2018-19-443, 2018-36-807, 2018-72-1418, 2018-19-455, 2018-72-1376, 2018-54-1137, 2018-54-1114, 2018-65-1249, and 2018-28-556 have good traits related to commercial root yield and root quality and may be recommended for human consumption.

Mapping phenotypic parameters linked to salt stress tolerance strategies in rice lines

Salinity is recognized as one of the main abiotic stresses, causing declines in the productivity of many crops, such as rice. Considering the importance of rice as a staple food crop, the generalized pattern of salinization in soils around the globe and the sensitivity of the crop to saline soils, the aim of this study was to evaluate the sensitivity / tolerance of upland rice lines. The upland rice lines used in this work were obtained from the Genetic Improvement Program of the Universidade Federal de Lavras. The experiment was carried out in a greenhouse, with a block design and factorial scheme, with 10 lines and four NaCl treatments (0, 3, 15 and 45 mmol·L-1) on the substrate. Parameters related to the emergence rate, seedling survival rate, growth and architecture, biomass allocation, gas exchange and productivity were evaluated. Salinity levels influenced the emergence and survival rates, especially at the highest levels of NaCl, with lines L1, L4 and L5 showing survival below 60%. These lines were excluded from the experiment, and the other seven lines were carried out until the end of the crop cycle. Grain weight per plant (GWP) was used as an indicator of greater tolerance to salinity, and lines L6, L7 and L8 showed outstanding performance under treatments with increased NaCl. L6 had the highest GWP, while L7 and L8 had less pronounced decreases with increasing NaCl doses. These three lines may be recommended for further studies about the impacts of NaCl on rice production.

Performance of superior potato clones under high and mild temperatures in tropical climate

AbstractPotato (Solanum tuberosum L.) is a cool weather crop and one of the most important vegetables in the world, which is cultivated in temperate, subtropical, and tropical climates. Nearly all cultivated areas in Brazil use cultivars from temperate countries, resulting in lower performances particularly due to higher temperatures. The aim of this study was to identify clones that yielded better than foreign cultivars, both under high and mild temperature conditions. The study assessed 57 clones from the potato breeding program of the Universidade Federal de Lavras (UFLA), Brazil, and five check cultivars (Agata, Asterix, Atlantic, Cupido, and Markies). We evaluated the agronomic performance using the total and marketable tuber yield, dry matter content (DM), season length, and external tuber quality, in four experiments designing in a random complete block, during the seasons 2014 and 2015. The genotypes' stability, as well as the discrimination between environments, was performed using the GGE‐Biplot method. Twenty heat‐tolerant clones responded favorably to mild temperatures. This breeding program has generated clones more productive and better looking than commercial cultivars, for the different market segments: two for the fresh market (GMR 17‐40; GMR 12‐10), four for frozen French fries (CBM 07‐78; CTB 03‐02; GMR 15‐42; SR2 35‐05) and seven for potato chips (CBM 16‐16; SR1 07‐16; GMR 03‐58; SR3 19‐24; SR2 57‐02; SR1 04‐06; SR3 32‐04).

Stability of potato clones resistant to potato virus Y under subtropical conditions

Abstract Brazilian potato production is based on cultivars originating from the USA and Europe; however, these cultivars were developed under different environmental conditions than those found in Brazil. The aim of this study was to evaluate the adaptability and stability of 18 potato clones (MLG), developed by the Universidade Federal de Lavras, and four cultivars in six environments in the state of Minas Gerais, Brazil. The following traits were evaluated: marketable tuber yield (MTY), specific gravity (SG), and tuber appearance (TA). Clones, environments, and the genotype × environment interaction had significant effects on all traits. The GGE-biplot explained 71.78, 98.13, and 62.86 % of the sum of squares from the G+G×E for MTY, SG, and TA, respectively. Three MLG clones had higher adaptability and stability, as well as better performance, than the cultivars, making them good candidates for release as cultivars.

First report of Aethalion reticulatum (Linnaeus, 1767) (Hemiptera: Aethalionidae) infesting plants of Coffea arabica (Linnaeus, 1753) (Rubiaceae)

Coffee is of great socio-economic importance, and in this scenario Brazil stands out as the largest producer and exporter of coffee beans. However, the coffee tree is susceptible to the attack of several insect pestshe main ones being the berry borer and leaf miner. However, other insects may be present in the crop, and their identification is important for the elaboration of mitigation measures. To date, the presence of the leafhopper Aethalion reticulatum (Linnaeus, 1767) (Hemiptera: Aethalionidae) in Coffea arabica (Linnaeus, 1753) (Rubiaceae) plants has not been reported in the literature. Thus, the present study aimed to describe the occurrence of A. reticulatum in arabica coffee plants on the Campus of the Universidade Federal de Lavras (UFLA), Lavras, Minas Gerais, Brazil. Key words: Fruit leafhopper; Insect pest; Coffee crop; Infestation.

Water retainer polymer in coffee plants deployment under different levels of irrigation

The use of water-retaining polymers may be a feasible alternative in regions with low water availability, as they has enhance the performance of coffee plants with more favorable anatomical characteristics to make physiological processes more efficient. However, the advantages of such use have been scarcely reported. Here, we studied the feasibility of using a water-retaining polymer to optimize irrigation water use during the establishment of a coffee plantation. A randomized block design was used in a factorial scheme (4 × 2) with three replications for a total of 24 experimental plots, each consisting of four pots, with one plant per unit. The experiment was installed in a greenhouse at the Coffee Science Department of the Universidade Federal de Lavras, Minas Gerais, Brazil, with four levels of irrigation (25%, 50%, 75%, and 100% of soil water at field capacity), with or without addition of the water-retaining polymer. Growth variables evaluated included: plant height, stem diameter, number of leaves, shoot and root dry weights, root volume and area. Additionally, gas exchange, leaf water potential, and leaf anatomy were analyzed. The use of water-retaining polymer during establishment of the coffee plantation ensured sufficient water supply, thus guaranteeing plant anatomical and physiological functionality and, consequently, a healthy, vigorous growth. Key words: Coffea arabica L.; Seedling establishment; Soil conditioner; Soil water availability; Water deficit.

Geographic distribution of the Ipomoea batatas (Convolvulaceae) pest, Bedellia somnulentella (Zeller) (Lepidoptera: Bedelliidae), in Minas Gerais state, Brazil

The microlepidoptera Bedellia somnulentella is a pest insect of Ipomoea batatas leaves, with the first report in South America, in the city of Diamantina, Minas Gerais state, Brazil, in 2018. The mining caterpillars of B. somnulentella cause damage to the leaf mesophyll of the host plant, Ipomoea batatas, an important crop which contributes to overcoming world food insecurity with high nutritional value. The objective of this work is to register the occurrence of B. somnulentella in I. batatas in the cities of Lavras and Salinas, located, respectively, in the southern and northern regions of Minas Gerais state, Brazil. The individuals of B. somnulentella were observed in field areas of the Universidade Federal de Lavras (21° 14′ S, 44° 58′ W, at an elevation of 919 masl) in Lavras and at the Instituto Federal do Norte de Minas Gerais (15° 27′ S, 44° 22′ W, at an elevation of 474 masl) in the city of Salinas. in production sites of the northeastern region These records increase the knowledge concerning the geographic distribution of this pest in the country and indicate the importance of developing strategic studies for pest contingency plans and integrated pest management (IPM). To monitor B. somnulentella in I. batatas, it is necessary to accompany the expansion of this pest in other regions, especially in the maof Brazil, a warmer region, and the southern states, with a milder climate.

Physicochemical parameters and volatile composition of cachaça produced in the state of Paraíba, Brasil

Cachaça is produced and marketed throughout Brazil to an extent that it has become a symbol of the country. To ensure the safety to consumers, the quality of the beverage must meet the legal standards set by Brazilian law. Nevertheless, reports of inadequacies are still common, and the complexity of its composition requires more detailed studies. This study sought to evaluate the chemical composition of cachaça produced in the state of Paraiba, determine the conformity with the parameters required by legislation, and identify volatile compounds present in these beverages. The cachaça samples were collected from the local commerce in their original packaging and sent to the Laboratório de Análise de Qualidade de Aguardente of the Universidade Federal de Lavras, in Lavras, Minas Gerais, Brazil. The parameters analyzed were those established by Brazilian legislation as indicators of quality. Volatile compounds were identified by mass spectrometry coupled to gas chromatography (GC-MS). Among the 20 samples analyzed, 17 were irregular with respect to at least one of the parameters established by the legislation. The complexity of the volatile composition has been proven by the fact that 57 compounds represented mainly by esters (ethyl decanoate and ethyl dodecanoate) and alcohols (3-methyl-1-butanol) were found.

A half century of a bean breeding program in the South and Alto Paranaíba regions of Minas Gerais

Abstract The success of bean (Phaseolus vulgaris L.) crops in Brazil is due to the development of new cultivars. The aim of the present study was to critically analyze the fifty years of a bean breeding program at the Universidade Federal de Lavras (UFLA) and estimate the genetic progress (GP) achieved for grain yield. The estimated genetic progress for grain yield was 0.35% per year, which is associated with visible improvement in plant architecture, resistance to some pathogens, and better carioca bean grain quality. The program was found to be efficient, generating 119 theses and 43 dissertations during the period under study. In addition, hundreds of articles have been published, especially studies aimed at improving the efficiency of genetic breeding programs. Over the past few years, partnerships with other public institutions in performing Value for Cultivation and Use tests have resulted in 12 recommended cultivars.

Leaf Anatomy of Apple Trees during Seasonal Periods under Subtropical Conditions

Water deficits are considered the primary environmental stress in agriculture, and improving the growth and production of plants under this stress is one of the primary goals of breeding and crop management programs. The apple tree is a plant that is negatively affected by water stress. Plants that develop under a water deficit may develop physiological and anatomical strategies to survive or even produce fruits in these environments. In view of the importance of and lack of studies of the leaf anatomy of apple trees in areas with a water deficit that are intended to support genetic improvement programs for this fruit either to introduce cultivars in regions with water deficits or to select potential progenies for future crosses, the aim of this study was to compare the anatomical characteristics of apple leaves from two distinct environments (water deficit and precipitation) under tropical conditions. Twelve fully expanded leaves were collected from seven apple cultivars (Eva, Rainha, Princesa, Julieta, Imperatriz, Baronesa, and Gala Real), which are planted in the experimental orchard at Universidade Federal de Lavras, during water deficit (September) and precipitation (February) seasons. Sixteen anatomical characteristics were evaluated in addition to the anatomical description of the apple leaves. The experimental design was completely randomized in a 7×2 factorial arrangement. The means were analyzed using the Scott-Knott method for grouping means at the 5% level of error probability. Genetic divergence, cultivar clustering and principal component analyses were also performed based on the anatomical characteristics evaluated during the two seasons. The apple leaves had anatomical characteristics that can favor the production of this fruit tree in areas experiencing water deficits within subtropical regions. According to their anatomical characteristics, there was genetic divergence among the apple cultivars studied here. The cultivars Gala Real, Eva, and Baronesa presented anatomical and morphological characteristics that showed adaptation potential in areas with water deficits.

Water distribution model for center pivot end gun sprinklers

ABSTRACT End gun sprinklers can increase the irrigated area by center pivot irrigation systems without a substantial investment. This study was carried out at the Universidade Federal de Lavras, MG state, Brazil, and aimed to describe and validate a water distribution model for center pivot end gun sprinklers. The gun sprinkler PLONA-RL250®, attached at the end point of a center pivot, was used to evaluate the model in field tests. The sprinkler working conditions considered were nozzle diameters of 14 x 6 mm, working pressure of 292 kPa, and four asymmetric wetted angle adjustments (95 + 20º; 90 + 90º; 60 + 60º; 45 + 45º). These tests were carried out for wind speed lower than 0.9 m s-1. The measured and simulated irrigation depths showed an average absolute difference of 0.65 mm and determination coefficients from 71.55 to 89.37%. Based on the confidence coefficient (c = 0.82) the model can be classified as very good (0.76 ≤ c ≤ 0.85). Sprinkler wetted angle adjustment of 110º (95 + 20º) resulted in uniform water distribution and, for effective radius of throw between 70 to 90% of the gun sprinkler´s radius of throw, this working condition resulted in Christiansen’s uniformity greater than 80%.

Associations between morphological and agronomic characteristics in garlic crop

ABSTRACT Correlations and path analysis between characteristics can aid the selection of important attributes in breeding programs. Thus, the objective of this work was to perform genotypic, phenotypic correlations and path analysis under commercial yield of garlic bulbs, depending on morphological and agronomic variables. The experiment was carried out in 2017 at the Universidade Federal dos Vales do Jequitinhonha e Mucuri and Universidade Federal de Lavras, using ten garlic genotypes, eight trials and two commercial cultivars, Caçador and Jonas. We evaluated: plant height; number of leaves, total bulb number; total bulb mass, total bulb yield, marketable bulb yield and number of cloves per bulb. The genotypic and phenotypic correlations were positive and significant between marketable yield of bulbs with bulb mass, total yield and number of cloves per bulb, indicating that selection based on these characteristics will help increase the yield of garlic. However, only the number of cloves per bulb had a direct effect and a relevant indirect effect on the marketable yield of garlic.